<!DOCTYPE html>
<html lang="en">
<body>
	<select id="s" name="s">
		<option value="option1">option one</option>
		<option value="option2">option two</option>
	</select>
	<script
		src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
	<script>
		(function($) {
			// Set the selected option in the select element to "option two" 
			$('select').val('option2');
			// Alerts "option2" 
			alert($('select').val());
		})(jQuery);
	</script>
</body>
</html>